Amphibious vehicle having the driving and floating screw rotors on its both sides



y 7, 1968 ISAMU 1T0 ETAL 3,381,650

AMPHIBIOUS VEHICLE HAV THE DRIVING AND FLOATING SCREW ROTORS ON ITS BOTH SIDES Filed Sept. 26, 1966 INVENTORS ISAMU ITOH KIYOSHI IMAMURA ATTORNEYS United States Patent 3,381,650 AMPHIBIOUS VEHICLE HAVING THE DRIVING AND FLOATING SCREW ROTORS ON ITS BOTH SIDES Isamu Itoh and Kiyoshi Imamura, Tokyo-to, Japan, as-

signors to Ishikawajima-Harima Jukogyo Kabushiki Kaisha, Tokyo-to, Japan, a Japanese company Filed Sept. 26, 1966, Ser. No. 582,075 Claims priority, application Japan, Dec. 17, 1965, 40/102,556 4 Claims. (Cl. 115-1) ABSTRACT OF THE DISCLOSURE A surface vehicle for traveling on land or water. The vehicle has front and rear pairs of screw rotors which are supported for rotary movement about their axes. Each screw rotor consists of an elongated rotor body which has an outer tapered end and a substantially constant diameter from the region of its outer end to its inner end, and each of the rotor bodies fixedly carries at its exterior a helically wound fin means which has a width which is but a small fraction of the diameter of the rotor body and which in the region of the inner end thereof has a plurality of convolutions of substantially the same diameter while in the region of the outer end of each rotor body the fin means has an end convolution of a substantially smaller diameter.

The present invention is related to an improvement of an amphibious vehicle having the driving and floating screw rotors on its both sides.

Conventionally a screw-rotor type amphibious vehicle has been provided which is able to run on marshy or boggy ground, having small supporting capacity, on the water or on the snow. On each side of a water-tight body is installed only one screw rotor with helical fins wound round it, the direction of the helix being opposite to each other, the said rotors being simultaneously or separately rotated by a motor provided in the said body so as to let the vessel move forward, backward or sidelong or make a turn. However, due to the fact that the rotors tend to slip on the hard ground, there is generated forward or backward drive, which prevents the vessel from moving straightly sideways but along a large circular arc; besides, since the friction coefiicient between the rotors and the surface of a hard ground is very great, the vessel not only is usable to move forward or backward unlike on the marshy ground or on the water but also cannot make a turn on a hard ground. Thus, it is quite a disadvantage of the conventional screw-rotor type amphibious vehicle that it easily loses command of action on a hard ground.

The present invention provides an amphibious vehicle which is free of the above mentioned shortcomings and displays excellent running performance on the ordinary ground or on the sand as well as on the marshy ground, on the water or on the snow.

Here is the explanation of an embodiment of the present invention with reference to the attached drawings.

FIG. 1 is the front view of an embodiment of the present invention, FIG. 2 the side view of the said embodiment, and FIG. 3 the plan of the said embodiment.

In the drawings, 1 refers to the water-tight body which is usually above the surface of the water, 2, 2, 2" and 2" refer to screw rotors with helical fins 3 fixedly wound on the surface of each rotor, the fins on the screw rotors 2' and 2" which are in the fore to the left and in the rear to the right respectively, when seen in the direction of the arrow in the drawing which indicates the direction of the forward movement of the vessel, are arranged clockwise,

Patented May 7, 1968 and the fins on the rest of the rotors 2 and 2" anticlockwise, the rotors being supported by means of the respective shafts at the right and left projection 4 and 4' of the body 1 and coupled with an engine in the engine room 5 through a reduction device (not shown in the drawings). Also, 6 refers to the drivers seat, and 7 to the place where men and cargo are to be loaded. Now, when the rotors 2 and 2" are rotated clockwise and the rotors 2 and 2" anticlockwise on a soft surface like on the marshy ground, on the water or on the snow, the leftward componcnt force and the rightward component force are equated to each other and the vessel moves forward. When the rotor 2 is rotated anti-clockwise and the rotor 2" clockwise on one hand, and the rotors 2 and 2" are prevented from rotating or the rotor 2' is rotated anticlockwise and the rotor 2" clockwise on the other hand, the vessel can make a turn to the left; if the direction of the above described rotation is reversed, the vessel turns to the right. While, on a hard surface such as on the ordinary ground or on the sand, if all the rotors are rotated clockwise at the same time, the rotors revolve like a wheel and the vessel moves sideways because the forward and the backward drive brought about by the slip of the rotors are mutually offset due to the fact that the fins are arranged on the fore rotor and on the rear rotor in the reversed direction on both sides of the vessel; if the rotors 2 and 2' are rotated clockwise on one hand,

and the rotors 2" and 2" are prevented from rotating or.

rotated anti-clockwise on the other hand the vessel turns to the right, and, if the directions of the respective rotation are reversed the vessel turns to the left.

Thus, it will be seen that with the invention there is provided a surface vehicle for traveling on solid land, water, or on surfaces which have the properties of both land and water. The vehicle includes the elongated vehicle body which has front and rear ends, shown respectively at the right and left of FIG. 3, and opposed sides. A pair of coaxial screw rotor means 2' and 2" extend along one of the sides of the vehicle body, while a second pair of coaxial screw rotor means 2 and 2" extend along the other side of the vehicle body. Thus, there are a pair of front screw rotor means 2' and 2 and a pair of rear screw rotor means 2" and 2'. In this way there is one set of diagonally opposed screw rotor means 2 and 2 and another set of diagonally opposed screw rotor means 2' and 2".

All of these screw rotor means respectively have inner ends located adjacent and directed toward each other at the opposite sides of the vehicle and outer ends directed away from each other and respectively situated at the ends of the vehicle body. The structure 4 and 4' forms a support means carried by the vehicle body for supporting all of the screw rotor means at their outer ends as well as at their inner ends for rotary movement about their axes, respectively, and it will be noted that each of the screw rotor means consists of an elongated rotor body which tapers in the region of its outer end and has a substantially constant diameter from the region of its outer end to its inner end, each of the rotor bodies fixedly carrying at its exterior a helically wound fin means 3 which has a width which is but a small fraction of the diameter of the rotor body and which has in the region of the inner end of each rotor body a plurality of convolutions of substantially the same diameter and in the region of the outer end of each rotor body an end convolution of substantially smaller diameter.

One of the sets of diagonally opposed rotor means has the fin means thereof wound in the same direction and the other of the sets of diagonally opposed rotor means has the fin means thereof wound in the same direction but oppositely to those of the one set. The fin means 3 consists of a single fin, and each rotor body has a truncated ovoidal configuration. Moreover, support means 4, 4' includes at the inner ends of the rotors a pair of support units 4 one of which is common to two coaxial rotors on one side of the vehicle and the other of which is common to the other two coaxial rotors at the other side of the vehicle.

The above described structure of the present invention has the advantages that the vessel can make a straight movement and a turn with ease even on a hard surface, as well as on a soft surface such as on the marshy field, etc. and that the vessel has an excellent mobility for it can move sideways at a high speed on a hard surface.

What We claim is:

1. In a surface vehicle for traveling on solid land, water, or on surfaces having the properties of both land and water, an elongated vehicle body having front and rear ends and opposed sides, two coaxial screw rotor means extending along each side of the vehicle body to provide a pair of front screw rotor means and a pair of rear screw rotor means which are respectively coaxial with said pair of front screw rotor means, and to provide two sets of diagonally opposed screw rotor means, said pairs of screw rotor means respectively having inner ends located adjacent and directed toward each other and outer ends directed away from each other and respectively situated at the ends of the vehicle body, support means carried by the vehicle body for supporting all of the screw rotor means at their outer ends as well as at their inner ends for rotary movement about their axes, respectively, and each screw rotor means consisting of an elongated rotor body which tapers in the region of its outer end and which has a substantially constant diameter from the region of said outer end to said inner end thereof, each of said rotor bodies fixedly carrrying at its exterior a helically wound fin means which has a width which is but a small fraction of the diameter of said rotor body and which has in the region of said inner end of each rotor body a plurality of convolutions of substantially the same diameter and in the region of said outer end of each rotor body an end convolution of a substantially smaller diameter, one of said sets of diagonally opposed rotor means having the fin means thereof wound in the same direction and the other of said sets of diagonally opposed rotor means having the fin means thereof wound in the same direction oppositely to those of said one set.

2. The combination of claim 1 and wherein said fin means consists of a single helically wound fin on each rotor body.

3. The combination of claim 1 and wherein each of said rotor bodies has a truncated ovoidal configuration.

4. The combination of claim 1 and wherein said support means includes at the inner ends of said rotor bodies a pair of support units one of which is common to two coaxial rotor bodies on one side and the other of which is common to the other two coaxial rotor bodies at the other side.

References Cited UNITED STATES PATENTS 2,495,643 1/1950 Pidgeon 115-19 XR 3,250,239 5/1966 Garate 115-19 XR ANDREW H. FARRELL, Primary Examiner. 

